This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. We are developing a new contact-free, small droplet ([unreadable]L-pL) deposition method using nanoliter drops and induction-based fluidics technique for MALDI mass spectrometry sample preparation. We have investigated a relationship between spot size (in the nL range, spot diameter e laser diameter) and the signal intensity. The signal intensities of the nanoliter spots and the normal spots were quantitatively compared for both ionic-liquid matrix and conventional solid matrices. We also used this approach for multiple spotting to increase sample concentration and, hence, sample signal intensity. This method will improve the signal intensity and sensitivity achieved by MALDI MS as well as allow a major fraction of trace samples to be saved for other experiments. This approach expands the application of MALDI MS to biological studies where sample quantity is often limited.